The Tarr Steps are a clapper bridge across the River Barle in the Exmoor National Park, Somerset, England. There are 17 spans across 50 metres (55 yd), the top slabs weigh 1-2 tons and are about 39 inches (99 cm) above normal water level. The largest slab is over 8 feet (2.4 m) long and is about 5 feet (1.5 m) wide. This is one of the best-known monuments on Exmoor. Its age is unknown, as several theories claim that Tarr Steps dates from the Bronze Age but others date them from around 1400 AD.